The present invention is drawn generally to a dual-sensor stethoscope that promotes anti-sepsis and stereoscopy. In particular, a stethoscope and retrofit device are disclosed wherein a generally T-shaped tube is used to support dual stethoscope heads that may be rotated away from a body independently.
Existing stethoscopes are currently utilized to auscultate or listen to physiologic sounds within the body. Auscultation with existing stethoscopes is currently performed by intermittently applying a stethoscope to the body surface through which the clinician hears various sounds. Intermittent auscultation may be thought of as a relatively benign procedure. However, several disadvantages and hazards are associated with the use of existing stethoscopes. First, patients undergoing surgery may have the sterile field invaded thereby risking infection in order for the clinician to auscultate the chest. To avoid cross-contamination between patients, many clinicians are forced to carry multiple stethoscopes. Additionally, even when a sterile stethoscope is used, it can transfer pathogens from a first location on a patient's body to a second location during typical auscultation. Furthermore, even in non-surgical environments, transmission of the cold virus is primarily through touch. A clinician's hand can touch the head of a stethoscope, which then touches a patient and vice versa so as to spread the virus.
Another disadvantage of known stethoscopes is that patients are frequently awakened and disturbed so that the clinician may apply a cold stethoscope to the patient's chest to monitor vital signs. Studies have shown serious developmental abnormalities in newborn infants who are frequently disturbed to auscultate heart and lung sounds with known stethoscopes. Another disadvantage of existing stethoscopes is that the quality of sound wave transmission is dependent upon an airtight seal between the stethoscope and the skin, typically requiring the clinician to touch, and possibly contaminate, the sensor. In the absence of an airtight seal, background noise is inadvertently detected and physiologic sound transmission is impaired. Finally, another disadvantage of existing stethoscopes is that most are not capable of generating positive or constructive interference of physiologic sound waves.
Stethoscopes are known which use two sound receiving heads but have several disadvantages. U.S. Pat. No. 4,706,777 to Baumberg discloses a stethoscope with two sound transmitting tubes connected to a valve. Depending upon the position of the valve, the clinician receives either mono or stereo sounds. However, the dual sensor heads require two-handed use and, even when receiving stereo sounds, the sound picked up by each sensor is transmitted through separate channels. As such, it would be desirable to have a dual-sensor stethoscope transmit sound through a common tube with constructive interference of sound waves resulting.
Such a dual-head stethoscope with sound transmission through a common tube for constructive interference of sound waves is disclosed in U.S. Pat. No. 4,997,055 to Grady. However, the dual-head arrangement of Grady uses a flexible tubing arrangement that requires use of both hands and requires additional stopcock elements to disable sound transmission from a head that is not in use.
U.S. Pat. Nos. 5,650,598 and 5,959,261 to Abelson disclose a dual-head stereophonic stethoscope provided with two conducting tubes and sound sensors, and two 3-way stopcocks. This arrangement enables the sound from one sensor to be conducted to one ear, while that from the second sensor is conducted to the other ear. One of the conducting tubes may be detached when the stethoscope is used for monophonic auscultation. Again, this arrangement lacks any constructive interference of sound waves, and the use of flexible tubing requires use of both hands for dual-head use and significant reconfiguration for single-head use.
Other patents disclose stethoscopes with multiple heads. In U.S. Pat. No. 3,124,211 to Cefaly and U.S. Pat. No. 2,722,989 to Tynan, the sound receiving heads are not capable of being used simultaneously. In U.S. Pat. No. 1,853,951 to Zala, U.S. Pat. No. 3,144,091 to Bodenger and U.S. Pat. No. 1,847,607 to Hardt, the sound receiving heads transmit sounds through separate tubes.